Turkey has summoned the Russian ambassador over images of a Russian soldier "brandishing a rocket launcher" as he traveled through Turkish waters. Tensions have worsened since Turkey downed a Russian warplane.

Turkish Foreign Minister Mevlut Cavusoglu summoned Andrey Karlov, the Russian ambassador to Ankara, on Monday, saying that such "provocation" as seen from the Russian serviceman on the Bosporus Strait - "has to end."

"I hope it is an isolated incident, it is not a right approach," he said, calling on Russia to act as a "more mature state."

The serviceman was allegedly photographed with a rocket launcher as the Russian ship passed through the Bosporus on its way to the Mediterranean. Turkey's private NTV channel reported the incident early on Sunday, while other media said it occurred on Friday.

Escalating tensions

Turkey downed a Russian jet closer to the Turkish-Syrian border on November 24, locking Moscow and Ankara into their worst crisis since the Cold War.

Cavusoglu renewed his call on Monday for Moscow and Ankara to overcome the growing tensions through diplomatic means, and for Russia to halt its economic sanctions against Turkey.

Turkish Deputy Prime Minister Mehmet Simsek warned on Monday that in the worst case scenario of "zero relations" with Russia, the Turkish economy risks losing $9 billion (8.3 billion euros).

ksb/jr (AFP, dpa)